1. Field of the Invention
The present invention pertains to a pattern forming method for bonding a resist film to, for example, the surface of a slider bar, which opposes a recording medium, and for forming the etching patterns of ABS planes on the resist film by exposing and developing the etching patterns to the resist film. More particularly, the present invention relates to a pattern forming method capable of forming etching patterns with a good dimensional accuracy.
2. Description of the Related Art
In a magnetic head device mounted on a hard disc apparatus, a slider is mounted at the extreme end of a gimbal formed of a leaf spring material. A thin film element having a recording and reproducing function is formed on an end of the slider.
FIG. 15 is a perspective view showing the slider with its surface, which opposes a recording medium, facing upward.
Referring to FIG. 15, a slider 30 is formed of a ceramic material such as alumina-titanium carbide, silicon (Si) or the like. An air groove 31 is formed on the surface of the slider 30 which opposes a hard disc as a recording medium, and rail portions 32, 32 are formed on both the sides of the air groove 31.
As shown in FIG. 15, the rail portions 32, 32 are formed to a prescribed crown shape, and the surfaces of the rail portions 32, 32 are arranged as ABS planes (floating planes) 33, 33. Further, inclining portions 34, 34 are formed on the end portions A of the rail portions 32, 32 on the leading sides thereof.
A thin film element 35 is disposed to the end face (end portion) of the slider 30 on the trailing side B thereof.
The thin film element 35 is composed of a reproducing MR head and a recording inductive head which are laminated on each other. The reproducing MR head has a magnetoresistive effect element layer such as an anisotropic magnetoresistive (AMR) element, a spin valve type thin film element and the like, and the recording inductive head is formed of a core and a coil each composed of a magnetic material.
As shown in FIG. 15, a plurality of terminal electrode portions 36, which are drawn from the thin film element 35, are formed on the end face B of the slider 30 on the trailing side thereof.
To make the slider 30, first, a ceramic material serving as the base material of the slider 30 is formed to a disc shape, and a plurality of thin film elements are sputtered on the ceramic material in parallel with each other.
Then, the ceramic material is sliced and a plurality of slender slider bars are formed from the ceramic material.
FIG. 16 is a perspective view showing one of the slider bars 40.
As shown in FIG. 16, a plurality of the thin film elements 35 are formed on a side 41 (end face on the trailing side) of the slider bar 40.
Numeral 42 shown in FIG. 16 is the opposing surface of the slider bar 40 which opposes the recording medium, and a plurality of the ABS planes 33, 33, which are shown in FIG. 15 and which are as many as the thin film elements 35, are formed on the opposing surface 42 through exposure and development.
How the etching patterns of the ABS planes were conventionally formed will be described with reference to FIG. 17.
First, as shown in FIG. 17, a plurality of the slider bars 40 (refer to FIG. 16) are disposed on a flat jig 45 with the opposing surfaces 42 thereof, which oppose the recording medium, facing upward.
At the time, the respective slider bars 40 are disposed at prescribed intervals 46 to prevent the thin film elements 35, which are formed on the sides of the slider bars 40 as shown in FIG. 16, from being damaged.
As shown in FIG. 17, the slider bars 40 are fixed on the jig 45 through an adhesive 47.
Next, a photosensitive resist film 48 is bonded to the surface of each slider bar 40.
Although the resist is also available in a liquid state in addition to the film state, the cost of the resist film is lower than that of a resist solution. Further, when the resist solution is used, it must be heated to remove the solvent contained in the resist solution after the surface of each slider bar 40 is coated with the resist solution. The use of the resist film is advantageous because the heating process is not necessary as well as the number of processes can be reduced.
When the etching pattern of each ABS plane is exposed on the surface of the photosensitive resist film 48 through a not shown exposure mask and further the etching pattern is processed in a developing process and a dry etching process, a plurality of the ABS planes 33, 33 are formed on the opposing surface 42 of each of the slider bars 40 as shown in FIG. 15.
A plurality of the sliders 30, which are shown in FIG. 15, can be obtained from the single slider bar 40 by cutting off the slider bar 40, which has a plurality of the ABS planes 33, 33 formed on the opposing surface 42 thereof, between the thin film elements 35.